Help. Procharger problem solving.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 844
Likes: 46
From: Southaven MS
Help. Procharger problem solving.
Thunder Racing just finished installation of my forged motor. The car is running good, but boost is falling off on the topend. It made 540rwhp at 5600rpm but then started falling down. Max boost was 11lbs. Below is a list of mods. Can anyone suggest things to check?
Forged 347
317 heads unported
manley ss valves
patriot dual springs
Voodoo cam 222/228 113+4 578/578
borla stingers
lg street headers
A&A FMIC
ECS meth kit
ECS bracket
D1SC head unit
Vortech race bypass
3.85 6 rib pulley
Forged 347
317 heads unported
manley ss valves
patriot dual springs
Voodoo cam 222/228 113+4 578/578
borla stingers
lg street headers
A&A FMIC
ECS meth kit
ECS bracket
D1SC head unit
Vortech race bypass
3.85 6 rib pulley
Last edited by redcycle13; Mar 29, 2007 at 06:42 PM.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 844
Likes: 46
From: Southaven MS
I was thinking it was belt slip too, but they said it wasn't. I wasn't there when they dynoed the car. I still have a feeling it is slipping, but I hate to argue with the experts when I wasn't around. They think it may be cavitation inside the blower due to inlet restriction. I don't think that's right.
Former Vendor
Joined: Dec 2006
Posts: 2,239
Likes: 1
I would upgrade your six rib to the eight rib assembly, as I can almost guarantee your problem is a result of belt slippage. I have seen it happen too many times when you start pushing the six rib assembly.
http://www.exoticperformanceplus.com...Car.php?car=40
This C5 has a D-1SC as well, pushing 16 lbs of boost.
What does your dyno graph look like? Is it jagged in the upper rpm range? Bob
http://www.exoticperformanceplus.com...Car.php?car=40
This C5 has a D-1SC as well, pushing 16 lbs of boost.
What does your dyno graph look like? Is it jagged in the upper rpm range? Bob
Last edited by EPP; Mar 30, 2007 at 06:28 AM.
Intermediate
Joined: Mar 2007
Posts: 43
Likes: 0
Ben-I sent you an email. Listen did they re-pin your crank with the new motor? Also with a 4.10 pulley I made 645-same combo just a tad more compression at a AFR of 10.1. I used either a K060873 ,K060876 or K060878. I can't remember 100% but there all here if you need them-it's bitch but it's tight-your belt is too loose-I think you said you used a 88.5 or 88.8? All the pulley's are the same and your using a smaller pulley so there's no way the belt your using is the same. Cavitation in the blower WTF is that? Man I know I'm going to have to fly down there and sort this out. Or sort out the PCV and belt stuff, take the car to another dyno and i can help you tune the car over the phone. Call me you got my #.
Drifting
Joined: May 2005
Posts: 1,697
Likes: 0
From: Stamford CT
something is going on your numbers are low for 11psi, look at your belts closely under power, i bet youll see some soking rubber, my old 8rib set up would smoke more than my tires with my F1R, i changed to ECS 10 rib. goodluck
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Drifting
Joined: Aug 2003
Posts: 1,313
Likes: 0
From: charlotte nc
??? I get 7# with a 3.85 pulley--how are yall so high in the boost???
I use to lose boost at gear changes in with my stock A4 and converter--about 3#!!! It doesn't move any with the RPM/vigilante setup. Is your car an A4? It might be going.
I use to lose boost at gear changes in with my stock A4 and converter--about 3#!!! It doesn't move any with the RPM/vigilante setup. Is your car an A4? It might be going.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 844
Likes: 46
From: Southaven MS
I can't help but think it's belt slip. What do you guy's think about swapping to a 4.10 pulley and retuning until I can get the 8 rib setup? You think I could make 11-12lb and 600rwhp. If so I think I'll just do that so i can get the car back until then.
Life Time NCM #2196
Joined: Sep 2004
Posts: 82,573
Likes: 1,684
From: Converse TX
Racer
Joined: Aug 2004
Posts: 353
Likes: 16
From: Twister Country
Don't forget.....
The A&A bracket still uses a stock style gates tensioner.
Those tensioners can have less then desired spring tension in them sometimes. They can also go bad overtime, and get weak. They are not all created equal.
First thing I would do, (and its a cheap part) would be to replace the tensioner. Then look into other factors like tear in a rubber that could be venting boost pressure.
EA
The A&A bracket still uses a stock style gates tensioner.
Those tensioners can have less then desired spring tension in them sometimes. They can also go bad overtime, and get weak. They are not all created equal.
First thing I would do, (and its a cheap part) would be to replace the tensioner. Then look into other factors like tear in a rubber that could be venting boost pressure.
EA
Life Time NCM #2196
Joined: Sep 2004
Posts: 82,573
Likes: 1,684
From: Converse TX
Don't forget.....
The A&A bracket still uses a stock style gates tensioner.
Those tensioners can have less then desired spring tension in them sometimes. They can also go bad overtime, and get weak. They are not all created equal.
First thing I would do, (and its a cheap part) would be to replace the tensioner. Then look into other factors like tear in a rubber that could be venting boost pressure.
EA
The A&A bracket still uses a stock style gates tensioner.
Those tensioners can have less then desired spring tension in them sometimes. They can also go bad overtime, and get weak. They are not all created equal.
First thing I would do, (and its a cheap part) would be to replace the tensioner. Then look into other factors like tear in a rubber that could be venting boost pressure.
EA
Burning Brakes
Joined: Aug 2006
Posts: 901
Likes: 1
From: Oxford PA
Melting Slicks
Joined: Sep 2005
Posts: 3,082
Likes: 0
From: eagle mountain utah
North Carolina is pretty close to sea level. I made 7 psi with a 3.7" pulley at 4200 feet elevation (thin air). Sea level is thicker air and you should see more than 7#. Do you have a restrictor plate, cam, heads or headers?